Visiting Chicago tries to avoid back-to-back defeats for the first time in almost two months when it opens a home-and-home set against the Celtics on Sunday night.

The Bulls (40-32), last in the NBA with 92.8 points per game, have averaged 83.3 in splitting their last four. Chicago came out with another ugly display in Friday's 91-74 loss to Portland, scoring 16 points in both the first and fourth quarters.

"Offensively we were just so bad," forward Mike Dunleavy told the team's official website after finishing with two points on 1-of-9 shooting. "Aside from not making shots, making the wrong decisions.

"Eventually it affected us on the defensive end, I think. I thought we got some good looks early on that didn't go down and it snowballed from there. Not our best; that's for sure."

While there wasn't any celebration, Chicago locked up its sixth consecutive playoff berth later that night when New York fell at Phoenix. The Bulls are in fourth place in the Eastern Conference, 1 1/2 games ahead of fifth-place Brooklyn.

"We pay attention to everything, it's our job to pay attention to what is going on," said center Joakim Noah, whose 7.3 assists per game this month rank first in the league among non-guards. "But what's important is us. There's 10 games left. We've been playing pretty good basketball. (Friday) is a bump in the road. We're all disappointed the way we played tonight.

Chicago, which hasn't suffered consecutive defeats since Feb. 1 and 3, will try to regroup against the Celtics. The Bulls have won eight of 11 in the series after taking this season's first matchup 94-82 on Jan. 2 behind 17 points, 11 rebounds and nine assists from Noah.

These teams meet again in Chicago on Monday.

Boston (23-49) just suffered a home-and-home sweep at the hands of Toronto, falling 105-103 on Friday for its third straight defeat and eighth in nine games. The Celtics trailed by 14 late in the third quarter, went up 101-97 with just over three minutes to go in the fourth and were then outscored 8-2 the rest of the way.

"We've got to play better throughout the game. There are times where we play well, like you've seen, and there are times when we struggle. We've just got to have a more consistent effort from everybody," Bayless said. "On the defensive end we've got to keep it to our fundamentals and our principles and hopefully it all works out."

Jeff Green, leading the team with 16.8 points per game, has averaged 11.2 in the last five since matching a season high with 39 against New Orleans on March 16.

He could struggle again versus Chicago, which has held him to 6.2 points and 27.9 percent shooting in the past five meetings.

Rajon Rondo owns a 6.8 assist-to-turnover ratio over his last eight games. Rondo is averaging 22.5 points and 10.0 assists in his last six against the Bulls.